This invention relates to a chair back, and in particular to a one piece chair back which bends to a curvature that approximates the curvature of the back when it bends to provide lumbar and upper back support.
It is well known that when a person leans back, as for example when sitting, the spine curves to accommodate the bending. Further, it is known that the spine does not bend in a smooth arc starting at the waist. Rather, the amount of curvature varies along its length. Thus, in the lumbar region the radius of bending is relatively small. As one moves up the spine the radius of bending increases until at the upper part of the spine there is virtually no bending.
Therefore, it would be desirable to have a chair back that would offer a high degree of support to the lumbar and upper back which bends to approximate the curvature of the back.
Further, it would be especially advantageous if such a chair were capable of being connected to a wide variety of chair bases and seats.
In addition, it would be advantageous if the chair back could support the spine when the person is twisting in the chair such as when leaning to the left or right such as when reaching across a desk.
Accordingly, with the foregoing in mind, the invention relates to an ergonomic chair back which includes an upwardly extending tab in the lumbar supporting part of the chair back and a plurality of downwardly directed generally curvilinear tabs that are disposed adjacent each other in an upwardly extending array from the lumbar supporting part of the chair back.